[v2,1/1] nvdimm: disable balloon
diff mbox

Message ID 1453740631-23259-1-git-send-email-den@openvz.org
State New
Headers show

Commit Message

Denis V. Lunev Jan. 25, 2016, 4:50 p.m. UTC
From: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>

NVDIMM for now is planned to use as a backing store for DAX filesystem
in the guest and thus this memory is excluded from guest memory management
and LRUs.

In this case libvirt running QEMU along with configured balloon almost
immediately inflates balloon and effectively kill the guest as
qemu counts nvdimm as part of the ram.

Counting dimm devices as part of the ram for ballooning was started from
commit 463756d03:
 virtio-balloon: Fix balloon not working correctly when hotplug memory

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: Stefan Hajnoczi <stefanha@redhat.com>
CC: Xiao Guangrong <guangrong.xiao@linux.intel.com>
CC: "Michael S. Tsirkin" <mst@redhat.com>
CC: Igor Mammedov <imammedo@redhat.com>
CC: Eric Blake <eblake@redhat.com>
CC: Markus Armbruster <armbru@redhat.com>
---
v2:
    - some rewordings, thanks to Eric Blake

 hw/mem/nvdimm.c          | 4 ++++
 hw/mem/pc-dimm.c         | 7 ++++++-
 include/hw/mem/pc-dimm.h | 1 +
 qapi-schema.json         | 5 ++++-
 4 files changed, 15 insertions(+), 2 deletions(-)

Comments

Igor Mammedov Jan. 26, 2016, 10:38 a.m. UTC | #1
On Mon, 25 Jan 2016 19:50:31 +0300
"Denis V. Lunev" <den@openvz.org> wrote:

> From: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
> 
> NVDIMM for now is planned to use as a backing store for DAX filesystem
> in the guest and thus this memory is excluded from guest memory management
> and LRUs.
> 
> In this case libvirt running QEMU along with configured balloon almost
> immediately inflates balloon and effectively kill the guest as
> qemu counts nvdimm as part of the ram.

Isn't issue in ballooning impl. and not of pc-dimm/nvdimm,
so make ballooning code to distinguish between kinds of memory
rather than adding not related fields to PCDIMMDeviceClass

why don't just move get_current_ram_size() into the sole user
virtio-balloon.c and ignore NVDIMMs when counting ram in
get_current_ram_size(),
that would be much less intrusive patch.

> 
> Counting dimm devices as part of the ram for ballooning was started from
> commit 463756d03:
>  virtio-balloon: Fix balloon not working correctly when hotplug memory
> 
> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
> Signed-off-by: Denis V. Lunev <den@openvz.org>
> CC: Stefan Hajnoczi <stefanha@redhat.com>
> CC: Xiao Guangrong <guangrong.xiao@linux.intel.com>
> CC: "Michael S. Tsirkin" <mst@redhat.com>
> CC: Igor Mammedov <imammedo@redhat.com>
> CC: Eric Blake <eblake@redhat.com>
> CC: Markus Armbruster <armbru@redhat.com>
> ---
> v2:
>     - some rewordings, thanks to Eric Blake
> 
>  hw/mem/nvdimm.c          | 4 ++++
>  hw/mem/pc-dimm.c         | 7 ++++++-
>  include/hw/mem/pc-dimm.h | 1 +
>  qapi-schema.json         | 5 ++++-
>  4 files changed, 15 insertions(+), 2 deletions(-)
> 
> diff --git a/hw/mem/nvdimm.c b/hw/mem/nvdimm.c
> index 4fd397f..4f4d29a 100644
> --- a/hw/mem/nvdimm.c
> +++ b/hw/mem/nvdimm.c
> @@ -27,9 +27,13 @@
>  static void nvdimm_class_init(ObjectClass *oc, void *data)
>  {
>      DeviceClass *dc = DEVICE_CLASS(oc);
> +    PCDIMMDeviceClass *ddc = PC_DIMM_CLASS(oc);
>  
>      /* nvdimm hotplug has not been supported yet. */
>      dc->hotpluggable = false;
> +
> +    /* ballooning is not supported */
> +    ddc->in_ram = false;
>  }
>  
>  static TypeInfo nvdimm_info = {
> diff --git a/hw/mem/pc-dimm.c b/hw/mem/pc-dimm.c
> index d5cdab2..e0f869d 100644
> --- a/hw/mem/pc-dimm.c
> +++ b/hw/mem/pc-dimm.c
> @@ -164,6 +164,7 @@ int qmp_pc_dimm_device_list(Object *obj, void *opaque)
>              MemoryDeviceInfo *info = g_new0(MemoryDeviceInfo, 1);
>              PCDIMMDeviceInfo *di = g_new0(PCDIMMDeviceInfo, 1);
>              DeviceClass *dc = DEVICE_GET_CLASS(obj);
> +            PCDIMMDeviceClass *ddc = PC_DIMM_GET_CLASS(obj);
>              PCDIMMDevice *dimm = PC_DIMM(obj);
>  
>              if (dev->id) {
> @@ -172,6 +173,7 @@ int qmp_pc_dimm_device_list(Object *obj, void *opaque)
>              }
>              di->hotplugged = dev->hotplugged;
>              di->hotpluggable = dc->hotpluggable;
> +            di->in_ram = ddc->in_ram;
>              di->addr = dimm->addr;
>              di->slot = dimm->slot;
>              di->node = dimm->node;
> @@ -205,7 +207,9 @@ ram_addr_t get_current_ram_size(void)
>          if (value) {
>              switch (value->type) {
>              case MEMORY_DEVICE_INFO_KIND_DIMM:
> -                size += value->u.dimm->size;
> +                if (value->u.dimm->in_ram) {
> +                    size += value->u.dimm->size;
> +                }
>                  break;
>              default:
>                  break;
> @@ -444,6 +448,7 @@ static void pc_dimm_class_init(ObjectClass *oc, void *data)
>      dc->props = pc_dimm_properties;
>      dc->desc = "DIMM memory module";
>  
> +    ddc->in_ram = true;
>      ddc->get_memory_region = pc_dimm_get_memory_region;
>  }
>  
> diff --git a/include/hw/mem/pc-dimm.h b/include/hw/mem/pc-dimm.h
> index d83bf30..3bcb505 100644
> --- a/include/hw/mem/pc-dimm.h
> +++ b/include/hw/mem/pc-dimm.h
> @@ -65,6 +65,7 @@ typedef struct PCDIMMDevice {
>  typedef struct PCDIMMDeviceClass {
>      /* private */
>      DeviceClass parent_class;
> +    bool in_ram;
>  
>      /* public */
>      MemoryRegion *(*get_memory_region)(PCDIMMDevice *dimm);
> diff --git a/qapi-schema.json b/qapi-schema.json
> index 2e960db..3cafa2b 100644
> --- a/qapi-schema.json
> +++ b/qapi-schema.json
> @@ -3922,6 +3922,8 @@
>  #
>  # @hotpluggable: true if device if could be added/removed while machine is running
>  #
> +# @in-ram: true if device is counted in current ram size (since 2.6)
> +#
>  # Since: 2.1
>  ##
>  { 'struct': 'PCDIMMDeviceInfo',
> @@ -3932,7 +3934,8 @@
>              'node': 'int',
>              'memdev': 'str',
>              'hotplugged': 'bool',
> -            'hotpluggable': 'bool'
> +            'hotpluggable': 'bool',
> +            'in-ram': 'bool'
>            }
>  }
>
Vladimir Sementsov-Ogievskiy Jan. 27, 2016, 10:06 a.m. UTC | #2
On 26.01.2016 13:38, Igor Mammedov wrote:
> On Mon, 25 Jan 2016 19:50:31 +0300
> "Denis V. Lunev" <den@openvz.org> wrote:
>
>> From: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
>>
>> NVDIMM for now is planned to use as a backing store for DAX filesystem
>> in the guest and thus this memory is excluded from guest memory management
>> and LRUs.
>>
>> In this case libvirt running QEMU along with configured balloon almost
>> immediately inflates balloon and effectively kill the guest as
>> qemu counts nvdimm as part of the ram.
> Isn't issue in ballooning impl. and not of pc-dimm/nvdimm,
> so make ballooning code to distinguish between kinds of memory
> rather than adding not related fields to PCDIMMDeviceClass
>
> why don't just move get_current_ram_size() into the sole user
> virtio-balloon.c and ignore NVDIMMs when counting ram in
> get_current_ram_size(),
> that would be much less intrusive patch.

Ok, will do.

>
>> Counting dimm devices as part of the ram for ballooning was started from
>> commit 463756d03:
>>   virtio-balloon: Fix balloon not working correctly when hotplug memory
>>
>> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
>> Signed-off-by: Denis V. Lunev <den@openvz.org>
>> CC: Stefan Hajnoczi <stefanha@redhat.com>
>> CC: Xiao Guangrong <guangrong.xiao@linux.intel.com>
>> CC: "Michael S. Tsirkin" <mst@redhat.com>
>> CC: Igor Mammedov <imammedo@redhat.com>
>> CC: Eric Blake <eblake@redhat.com>
>> CC: Markus Armbruster <armbru@redhat.com>
>> ---
>> v2:
>>      - some rewordings, thanks to Eric Blake
>>
>>   hw/mem/nvdimm.c          | 4 ++++
>>   hw/mem/pc-dimm.c         | 7 ++++++-
>>   include/hw/mem/pc-dimm.h | 1 +
>>   qapi-schema.json         | 5 ++++-
>>   4 files changed, 15 insertions(+), 2 deletions(-)
>>
>> diff --git a/hw/mem/nvdimm.c b/hw/mem/nvdimm.c
>> index 4fd397f..4f4d29a 100644
>> --- a/hw/mem/nvdimm.c
>> +++ b/hw/mem/nvdimm.c
>> @@ -27,9 +27,13 @@
>>   static void nvdimm_class_init(ObjectClass *oc, void *data)
>>   {
>>       DeviceClass *dc = DEVICE_CLASS(oc);
>> +    PCDIMMDeviceClass *ddc = PC_DIMM_CLASS(oc);
>>   
>>       /* nvdimm hotplug has not been supported yet. */
>>       dc->hotpluggable = false;
>> +
>> +    /* ballooning is not supported */
>> +    ddc->in_ram = false;
>>   }
>>   
>>   static TypeInfo nvdimm_info = {
>> diff --git a/hw/mem/pc-dimm.c b/hw/mem/pc-dimm.c
>> index d5cdab2..e0f869d 100644
>> --- a/hw/mem/pc-dimm.c
>> +++ b/hw/mem/pc-dimm.c
>> @@ -164,6 +164,7 @@ int qmp_pc_dimm_device_list(Object *obj, void *opaque)
>>               MemoryDeviceInfo *info = g_new0(MemoryDeviceInfo, 1);
>>               PCDIMMDeviceInfo *di = g_new0(PCDIMMDeviceInfo, 1);
>>               DeviceClass *dc = DEVICE_GET_CLASS(obj);
>> +            PCDIMMDeviceClass *ddc = PC_DIMM_GET_CLASS(obj);
>>               PCDIMMDevice *dimm = PC_DIMM(obj);
>>   
>>               if (dev->id) {
>> @@ -172,6 +173,7 @@ int qmp_pc_dimm_device_list(Object *obj, void *opaque)
>>               }
>>               di->hotplugged = dev->hotplugged;
>>               di->hotpluggable = dc->hotpluggable;
>> +            di->in_ram = ddc->in_ram;
>>               di->addr = dimm->addr;
>>               di->slot = dimm->slot;
>>               di->node = dimm->node;
>> @@ -205,7 +207,9 @@ ram_addr_t get_current_ram_size(void)
>>           if (value) {
>>               switch (value->type) {
>>               case MEMORY_DEVICE_INFO_KIND_DIMM:
>> -                size += value->u.dimm->size;
>> +                if (value->u.dimm->in_ram) {
>> +                    size += value->u.dimm->size;
>> +                }
>>                   break;
>>               default:
>>                   break;
>> @@ -444,6 +448,7 @@ static void pc_dimm_class_init(ObjectClass *oc, void *data)
>>       dc->props = pc_dimm_properties;
>>       dc->desc = "DIMM memory module";
>>   
>> +    ddc->in_ram = true;
>>       ddc->get_memory_region = pc_dimm_get_memory_region;
>>   }
>>   
>> diff --git a/include/hw/mem/pc-dimm.h b/include/hw/mem/pc-dimm.h
>> index d83bf30..3bcb505 100644
>> --- a/include/hw/mem/pc-dimm.h
>> +++ b/include/hw/mem/pc-dimm.h
>> @@ -65,6 +65,7 @@ typedef struct PCDIMMDevice {
>>   typedef struct PCDIMMDeviceClass {
>>       /* private */
>>       DeviceClass parent_class;
>> +    bool in_ram;
>>   
>>       /* public */
>>       MemoryRegion *(*get_memory_region)(PCDIMMDevice *dimm);
>> diff --git a/qapi-schema.json b/qapi-schema.json
>> index 2e960db..3cafa2b 100644
>> --- a/qapi-schema.json
>> +++ b/qapi-schema.json
>> @@ -3922,6 +3922,8 @@
>>   #
>>   # @hotpluggable: true if device if could be added/removed while machine is running
>>   #
>> +# @in-ram: true if device is counted in current ram size (since 2.6)
>> +#
>>   # Since: 2.1
>>   ##
>>   { 'struct': 'PCDIMMDeviceInfo',
>> @@ -3932,7 +3934,8 @@
>>               'node': 'int',
>>               'memdev': 'str',
>>               'hotplugged': 'bool',
>> -            'hotpluggable': 'bool'
>> +            'hotpluggable': 'bool',
>> +            'in-ram': 'bool'
>>             }
>>   }
>>

Patch
diff mbox

diff --git a/hw/mem/nvdimm.c b/hw/mem/nvdimm.c
index 4fd397f..4f4d29a 100644
--- a/hw/mem/nvdimm.c
+++ b/hw/mem/nvdimm.c
@@ -27,9 +27,13 @@ 
 static void nvdimm_class_init(ObjectClass *oc, void *data)
 {
     DeviceClass *dc = DEVICE_CLASS(oc);
+    PCDIMMDeviceClass *ddc = PC_DIMM_CLASS(oc);
 
     /* nvdimm hotplug has not been supported yet. */
     dc->hotpluggable = false;
+
+    /* ballooning is not supported */
+    ddc->in_ram = false;
 }
 
 static TypeInfo nvdimm_info = {
diff --git a/hw/mem/pc-dimm.c b/hw/mem/pc-dimm.c
index d5cdab2..e0f869d 100644
--- a/hw/mem/pc-dimm.c
+++ b/hw/mem/pc-dimm.c
@@ -164,6 +164,7 @@  int qmp_pc_dimm_device_list(Object *obj, void *opaque)
             MemoryDeviceInfo *info = g_new0(MemoryDeviceInfo, 1);
             PCDIMMDeviceInfo *di = g_new0(PCDIMMDeviceInfo, 1);
             DeviceClass *dc = DEVICE_GET_CLASS(obj);
+            PCDIMMDeviceClass *ddc = PC_DIMM_GET_CLASS(obj);
             PCDIMMDevice *dimm = PC_DIMM(obj);
 
             if (dev->id) {
@@ -172,6 +173,7 @@  int qmp_pc_dimm_device_list(Object *obj, void *opaque)
             }
             di->hotplugged = dev->hotplugged;
             di->hotpluggable = dc->hotpluggable;
+            di->in_ram = ddc->in_ram;
             di->addr = dimm->addr;
             di->slot = dimm->slot;
             di->node = dimm->node;
@@ -205,7 +207,9 @@  ram_addr_t get_current_ram_size(void)
         if (value) {
             switch (value->type) {
             case MEMORY_DEVICE_INFO_KIND_DIMM:
-                size += value->u.dimm->size;
+                if (value->u.dimm->in_ram) {
+                    size += value->u.dimm->size;
+                }
                 break;
             default:
                 break;
@@ -444,6 +448,7 @@  static void pc_dimm_class_init(ObjectClass *oc, void *data)
     dc->props = pc_dimm_properties;
     dc->desc = "DIMM memory module";
 
+    ddc->in_ram = true;
     ddc->get_memory_region = pc_dimm_get_memory_region;
 }
 
diff --git a/include/hw/mem/pc-dimm.h b/include/hw/mem/pc-dimm.h
index d83bf30..3bcb505 100644
--- a/include/hw/mem/pc-dimm.h
+++ b/include/hw/mem/pc-dimm.h
@@ -65,6 +65,7 @@  typedef struct PCDIMMDevice {
 typedef struct PCDIMMDeviceClass {
     /* private */
     DeviceClass parent_class;
+    bool in_ram;
 
     /* public */
     MemoryRegion *(*get_memory_region)(PCDIMMDevice *dimm);
diff --git a/qapi-schema.json b/qapi-schema.json
index 2e960db..3cafa2b 100644
--- a/qapi-schema.json
+++ b/qapi-schema.json
@@ -3922,6 +3922,8 @@ 
 #
 # @hotpluggable: true if device if could be added/removed while machine is running
 #
+# @in-ram: true if device is counted in current ram size (since 2.6)
+#
 # Since: 2.1
 ##
 { 'struct': 'PCDIMMDeviceInfo',
@@ -3932,7 +3934,8 @@ 
             'node': 'int',
             'memdev': 'str',
             'hotplugged': 'bool',
-            'hotpluggable': 'bool'
+            'hotpluggable': 'bool',
+            'in-ram': 'bool'
           }
 }